Platform-scale.



Patented m. 23, I900.

W. F. STIMPSUN.

PLATFORM SCALE.

(Application filed Apr. 25, 1898.) (No Model.) 2 Sheets-Sheet l.

Inn 67070? UNITED STATES WALTER F. STIMPSON,

OF MILAN, MICHIGAN.

PLATFORM-SCALE.

SPECIFICATION forming part of Letters Patent No. 641,904, dated January 23, 1900.

Application filed April 25, 1898.

To aZZ whom it may concern.-

Be it known that I, WALTER F. STIMPSON, a citizen of the United States, residing at Milan, in the county of l/Vashtenaw and State of Michigan, have invented certain new and useful Improvements in Platform-Scales, of which the following is a specification,reference being had therein to the accompanying drawings.

The invention relates to the construction of a platform-scale, and particularly to that class of platform-scale consisting of a combined truck and scale and commonly called truckscales.

The invention relates more particularly to the following points: first, to the means for raising the platform from the pivots; second, to the means for shifting the platform longitudinally when it is lowered; third, in the means for locking the beam when the platform is in its operative position; fourth, in the construction of the levers, and, fifth, in the construction, arrangement, and combination of the various parts, all as more fully hereinafter described. I

In the drawings, Figure l is a bottom plan View showing my truck-scale. Fig. 2 is a vertical central longitudinal section therethrough. Fig. 3 is a cross-section on line 0c 00 in Fig. 1. Fig. 4 is a section on line 3 y, Fig. 3. Fig. 5 is a detail section illustrating the construction of the lifting means for the platform. Fig. 6 is a cross-section at the beam end of the scale, showing the beam and its locking mechanism in elevation. Fig. 7 is a detail sectional elevation showing the actuating device for the platform-raising shaft and the locking means for the beam.

In the'prior state of the art there have been made so-called drop-lever scalesthat is, scales in which the pivots of the levers are dropped away from the bearing-feet of the platform, so that the articles thrown on the platform will not affect such pivots. Such scales have also been made in which the levers were held stationary or without such raising or lowering devices and the platform has been raised or lowered in relation to the pivots or the levers. My scale belongs to this last-named class so far as that feature is concerned and is an improvement over the prior devices because I have been able to use a single central shaft or a single central lifting de- Serial No. 678,737. (No model.)

vice which simplifies and cheapens the construction and also assists in simplifying the features which are combined with this par ticular type of scale.

A represents the frame.

B is the long lever, and O is the short lever, these levers being supported in the usual manner from the frame. The two levers are connected together centrally, as shown in Fig. 1, and the long lever is connected to the weighing-beam D, which in this case is arranged between the handles E of the truck. The truck is formed by the wheels F on suitable brackets on the forward end and feet G at the other end and is preferably provided with the usual nose-piece H. The construction I have shown is, in effect, an ordinary warehouse-truck with a scale supported on the frame thereof, I being the platform, which is provided with suitable bearing-feet a, resting on the pivots b of the levers.

Arranged along the middle of the platform and longitudinally thereof is a shaft J, journaled in hearings on the frame and provided with means for rocking it, such as the lever K at one end. This shaft I have shown as running longitudinally of the platform; but it may, if desired, be arranged transversely at the middle. This shaft is provided with the cams L, which are adapted to bear against the platform when the shaft is rocked and lift its bearing-feet from the pivots of the levers. If thus lifted by supports on the middle, it is evident that the platform would tip or tilt, and to prevent this I arrange the fingers or lugs M at or near the corners or on opposite sides of the 1ifting-cams,'which, when the platform is raised, strike and bear against stationary portions of the frames. Now inasmuch as one side cannot lower without raising the other it is evident that such fingers 0r bearings on opposite sides of this liftingpoint bearing upwardly would prevent the tilting of the platform and lock it tightly in position, provided the shaft J is rocked to cause the cams to lift the platform;

In the ordinary use of a truck-scale it frequently happens that the operator uses the device as a truck to pick a heavy bag or other article by engaging the nose H under the article, tipping it backonto the truck, and then turning the truck in the horizontal position,

and in this use the article usually rests against the nose-piece, as shown at N in Fig. 4. The parts being arranged as shown in the last figure referred to, it will be readily ob served that if the platform were lowered directly down part of the load would be sustained on the nose-piece, and therefore the shown in Fig. 4:, will be moved away therefrom before the platform rests upon the levers in the weighing position. By this very simple construction of a spiral cam I am enabled to effect this longitudinal shifting without any material additional expense.

When the device is to be used as a truck, the platform will be raised and locked in the manner described, and it is desirable to lock thebeam also; and as the beam is to be used only when the scale is in weighing condition I prefer and have here shown a locking means for the beam, which is actuated by and upon the operation of the means for raising and lowering the platform. 7

P is a lock-actuating cam on the shaft J, which engages into the yoke P on'jone end of a lever Q, the other end of which is offset or bent, so as to extend into the path of the weighing-beam D, as plainly shown in Figs. 1, 6, and 7. When the scale is in its weighing condition, this arm of the lever is out of contact with the beam and the beam is free to oscillate without touching the same. When the platform is moved into its inoperative position, the rocking of the shaft J through the lever K will also rock the lever Q, as shown in full and dotted lines in Fig. 7, and cause the end of that lever to press the beam upon the stop R, and thereby lock it against movement while the parts are in this position."

It is desirable, if not necessary, to lock the shaft J in its outer extreme positions, and this I accomplish by so constructing'the yoke P that when the cam P is turned in the position shown in Fig. 7 in full lines the large part of the cam will rock in the yoke, and thereby not only look the lever in position, but the lever will, in effect, lock the cam and the shaft in position, and the further rotation of the shaft will again rock the cam in the yoke, so that without the use of additional parts I am enabled to lock the shaft and its connected parts in its adjusted positions.

The levers I preferably form as follows: I bend metal bars into substantially V shape to form the middle portion a thereof;and then I secure to the ends, as by casting, the pivotholding sections 1), which are preferably cast with the holes therein for the pivots, which may be fitted in the usual manner. I deem this construction preferable to bending the metal bars upon themselves, because I am enabled to cast the holes therein, and thereby save labor, and also there is less danger of the pivot working out of its true position.

The weighing-beam D, which, as heretofore stated, is connected to the long lever B, is a double beam comprising upper and lower arms on which are arranged, respectively, in the usual manner weighing-poises A and B The upper arm has marked thereon, preferably, graduations from I to 100, while the lower arm has marked thereon graduations 100 and 200. When the article to be weighed is greater than one hundred pounds, both poises are employed.

The reference-letter O designates the counterpoise, which is arranged upon the lower arm, by means of which the double beam is properly adjusted, and, if desired, this latter poise may constitute a tare-poise.

I believe I am the first to have means which separate the levers from the platform in such a scale as this and by the actuation of the separating means to lock the beam against oscillation. I believe I am the first also to have middle lifting devices for the platform and means to prevent the tilting by moving the platform into engagement with stationary bearings on opposite sides of the lifting-points, as well as of the other features more specificallypointed out in the claims.

What I claim as my invention is- 1. In a scale, the combination of the levers, the platform resting on the Iever-pivots,means for lifting the platform from the pivots, said means being arranged centrally and longitudinally of the platform, a single actuating device for operating the raising means, and side bearings independent of said raising means for preventing the tilting of the platform members, comprising lugs upon the platformcorners and cooperating shoulders upon the scale-frame.

2. In a platform truck-scale, the combination of a truck, the scaledevers, a platform mounted upon the truck normally out of engagement with the lever-pivots and adapted to be lowered into engagement with said pivots and to be shifted longitudinally, and means for lowering and longitudinally shifting the platform.

8. In a platform truck-scale, the combination of a truck, the scale-levers, a platform mounted upon the truck normally out of engagement with the lever-pivots, and adapted to be lowered into engagement with said pivots and to be shifted longitudinally, and means for simultaneously lowering and shifting the platform.

4. In a platform truck-scale, the combination of the truck, a nose-piece thereon, the scale-levers, a platform mounted upon the truck normally out of engagement with the lever-pivots, connection between the platform and the truck, permitting the frame to be gradually lowered into engagement with the pivots and to be shifted longitudinally away from the nose-piece, and a single actuating device for operating the connections adapted to simultaneously lower and shift the platform.

5. In a platform-scale, the combination of the frame, the levers, the platform, a longitudinal shaft journaled in the frame, across the middle line of the platform, worm-shaped cams thereon and bearings on the platform with which said cams engage to raise and lower and longitudinally move the platform.

6. In a platform-scale,the combination with the beam, the levers, and the platform, means for separating the platform-bearing and the pivots of the scale-levers, and a locking means for the beam, operated by and upon the actuation of said separating means.

7. In a platform-scale,the combination with the beam, the levers and the .platform, of a raising and lowering device for the platform and a device for locking the beam which is operated when the platform is raised.

8. In a platf0rm-scale,the combination with the beam, the levers, the platform resting upon the pivots thereof, of means for raising the platform from, and lowering it upon the pivots, a lock to prevent the oscillations of the weighing-beam, and a common actuating device for the platform and for the beamlocking device, arranged so that as the platform is raised from the pivots the beam is locked, and as the platform is lowered into weighing position, the beam is released.

In testimony whereof I affix my signature in presence of two witnesses.

WALTER F. STIMPSON.

Witnesses:

M. B. ODoonER'rY, OTTO F. BARTHEL. 

